Rubicon (D9F7) Rabbit mAb

Autophagy is a catabolic process for the autophagosomic-lysosomal degradation of bulk cytoplasmic contents (1,2). Autophagy is generally activated by conditions of nutrient deprivation but is also associated with a number of physiological processes, including development, differentiation, neurodegeneration, infection, and cancer (3). The molecular machinery of autophagy was largely discovered in yeast and is directed by a number of autophagy-related (Atg) genes. These proteins are involved in the formation of autophagosomes, which are cytoplasmic vacuoles that are delivered to lysosomes for degradation. The class III type phosphoinositide 3-kinase (PI3K) Vps34 regulates vacuolar trafficking and autophagy (4,5). Multiple proteins associate with Vps34, including p105/Vps15, Beclin-1, UVRAG, Atg14, and Rubicon (6-12). Atg14 and Rubicon were identified based on their ability to bind to Beclin-1 and participate in unique complexes with opposing functions (9-12). Rubicon, which localizes to the endosome and lysosome, inhibits Vps34 lipid kinase activity; knockdown of Rubicon enhances autophagy and endocytic trafficking (11,12). In contrast, Atg14 localizes to autophagosomes, isolation membranes, and ER and can enhance Vps34 activity. Knockdown of Atg14 inhibits starvation-induced autophagy (11,12). 1.Reggiori, F. and Klionsky, D.J. (2002) Eukaryot Cell 1, 11-21. 2.Codogno, P. and Meijer, A.J. (2005) Cell Death Differ 12 Suppl 2, 1509-18. 3.Levine, B. and Yuan, J. (2005) J Clin Invest 115, 2679-88. 4.Corvera, S. (2001) Traffic 2, 859-66. 5.Yan, Y. and Backer, J.M. (2007) Biochem Soc Trans 35, 239-41. 6.Stack, J.H. et al. (1995) J Cell Biol 129, 321-34. 7.Zeng, X. et al. (2006) J Cell Sci 119, 259-70. 8.Liang, C. et al. (2006) Nat Cell Biol 8, 688-99. 9.Itakura, E. et al. (2008) Mol Biol Cell 19, 5360-72. 10.Sun, Q. et al. (2008) Proc Natl Acad Sci USA 105, 19211-6. 11.Zhong, Y. et al. (2009) Nat Cell Biol 11, 468-76. 12.Matsunaga, K. et al. (2009) Nat Cell Biol 11, 385-96.